Dahanu is a town on the border of Gujarat and Maharashtra. It is a place on coastal region of Arabian Sea and lies between 19°, 58' North longitude and 72°, 42' East latitude. The reliance thermal power station, Nu- clear Atomic Centre, Tarapur and Industrial area are nearby Dahanu. As small decapods and other organisms being food for fishes, help the growth of fishes in that catchment area. The success of species depends on the viability of eggs and the rate of development of egg. A variety of environmental factors such as temperature, rainfall, photoperiod, salinity, dissolved gases and chemicals in seawater in combination with these factors are closely related to species survival. But the effluents released by thermal power station in this area affected by productivity of economically important crustaceans. Therefore, efforts are made to study the role of physicochemical parameters such as pH, salinity, alkalinity, total dissolved solids etc. on the reproduction of marine prawn, Penaeus canaliculatus. In the present investigation, it was observed that the total dissolved solids and BOD, shown high values at the initiation of reproductive phase of marine prawn. Other parameters such as pH, alkalinity was helpful in increasing planktons in surrounding water. Thus avail- ability of abundant food favorable environmental factors resulted in successful breeding of Penaeus canaliculatus.